If your external filter is leaking, don’t worry — in most cases, the cause can be quickly identified and resolved. Please follow the steps below to diagnose the issue and prevent further damage.

Step 1: Stop the Water Flow and Identify the Source

  • Immediately disconnect the filter from the mains.

  • Identify where the leak is coming from — top, bottom, or pipework.

  • If water is still flowing, shut off taps and place the unit in a bucket or tray to catch excess water.

Step 2: Inspect the Motor Head O-Ring

  • Remove the motor head and check the large O-ring that seals the head to the canister.

  • Ensure it is:

    • Not cracked, worn, or perished

    • Properly seated in its groove

    • Lightly lubricated with aquarium-safe grease

Dry, twisted, or damaged O-rings are a leading cause of leaks after cleaning.

Step 3: Check the Hose Adaptors and Clips

  • Make sure hose adaptors are fully inserted and clipped in securely.

  • Inspect for cracks or warping.

  • On the underside of each adaptor, check the two small clear O-rings for signs of wear or damage.

Step 4: Examine Pipework and Seals

  • Confirm that all hoses are:

    • Firmly connected

    • Not kinked or pulled

    • Properly sealed with undamaged and lubricated O-rings

Loose or unsealed connections may cause leaks under pressure.

Step 5: Order Replacement Parts if Needed

If any part is visibly damaged or worn, you can order replacements from our website.
Click here to view spare parts

Still Leaking?

If the issue persists:

Important Safety Reminder

Always disconnect the unit from the mains electricity before opening or servicing the filter.
Refer to your product’s instruction manual for full safety and troubleshooting guidance. If you no longer have this, you will find a copy listed on the main product page on the website.